Method of preparing color-plates for printing.



No. 753,746. PATENTBD MAR. 1, 1964.

c. N. SMITH.

METHGD 0F PREPARING COLOR PLATES IOR PRINTING.

APPLICATION IILEDJAN. 10. 1 903.

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-PATBNTED MAR; I',`19o4. o. N. SMITH. METHOD 0T PRBPARING GoLoR PLATESFOR PRINTING.

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APPLICATION FILED JAN. 10. 1903.

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H93" VYnmw snqoq amUoY dama A TTOHNEY` No. 753,746. i

UNITED STATES Patented March 1; 1904.

PATENT OEEICE.

CHRIS N. SMITH, OF ELCrIN, ILLINOIS, ASSIGNOR TO THE DAVID C. COOKPUBLISHING COMPANY, OF ELGIN, ILLINOIS.

METHOD OF PREPARING COLOR-PLATES FOR PRINTING.

SPECIFICATION f01 m11g part 0f Letters yPatent No. 753,746, dated March1, 1904.

Apphcation filed January 1o, 41903.

To all whom it mag/concern.-

Be it known that I, CHRIS N. SMITH, residing at Elgin, in the county ofKane and State of Illinois, have invented a new and Improved Method ofPreparing Color-Plates for Printing, of which the following is aspecification.

and by which the plate can be wholly prepared without the aid of skilledlabor and the engraving and etching done by hand by eX- periencedengravers, required in the present methods of preparing color-plates, isentirely dispensed with.

As is well known, in the methods now commonly employed for preparingcolor-plates for letter-press printing it is usual to transfer allcolors on a separate plate, which is.

g plates are half-tones or solid, the filling a has then engraved andetched before it may-be ready for electrotyping.

My improved method in its generic nature differs from the methods nowgenerally employed in that no etching or engraving of the plate isrequired and in thatthe treatment of the plate is such that it is madepossibleand perfectly practical to make from one to four colors by myprocess.

With the above and other objects in mind my invention consists in themethod of preparing a relief-plate for color-printing, hereinafter fullydescribed, and specifically pointed out in the appended claims.

In order that my invention may be better understood, attention isdirected to the accompanying drawings, in which- Figure 1 shows aportion of an original relief-plate for letter-press printing which maybe in the nature of an electrotype, stereotype, or an ordinarytype-form. Fig. 2 is a representation of the plate shown in Fig. l afterreceiving the first step of my method-that of Serial No. 138,542. (Nospecimens.)

applying the composition for filling the face of the plate at the placeswhere it is intended to make the color impressions. Fig. 3 shows thesaid plate after it has received the second step of my method-that ofcleaning away the filling at the desired points. Fig. 4 illustrates aslight modification of my method; and Fig. 5 is a section of a portionof a plate constructed in accordance. with my invention with the filledsurfaces a", hereinafter referred to, in a plane parallel with butslightly higher than the remaining surfaces of thev plate.

Fig. a'isasection of a portion of a plate,

illustrating a part of the filling cut away for the purposes hereinafterexplained. f

The original plate, either an electrotype, a stereotype, or an ordinarytype-form, is filled at the points where it is desired to have theimprints in colors with wax or any other composition that will stand theheat like wax. -A .This filling (indicated by a) is then smoothed o downin aparallelplanewith the printing-sur` face of the plate and ispreferably built up a little higher than thesaid surface, asdiagrammatically indicated by w in, Fig. 5. When the its surface aburnished smooth, as shown, at

. the parts l la, whereby to present a solid inktaking surface; butwhere the cuts or designs i are open the wax from that part thereof notintended to appear in color is cut away down `to the metal surface l, asindicated by 2 in So far as described it will be readily apparent thatby reason of having `to remove the soft filling rather than the hardmetal a great advantage is obtained over theoldmethod, in

which the cutting away of the metal is 'necessary to eliminate from theplate the impression-surface not to appearcolored in the print, it beingobvious, however, that `in the event of the built-up portion or fillinga .being shallow-that is, its outer or impression surface beingsubstantially iush with the metal impression-surface of the plate-themetal at the blank or open spaceszfrom which the wax lilling is to beremoved may also be cut away to have the desired results, as shown inFig. 4.

When the cuts of the plates are solid-that is, when it is desired toprint a solid color entirely over the cut or illustration indicated by 5in Fig. l-the wax filling is smoothed off solid with theprinting-surface of the cut, so as to completely fill all Vof the white7spaces or stippled indentations when the cutis a halftone, and the saidsurface is burnished whereby to produce, as it were, a solid smoothprinting-block, as indicated by 5 in Fig. 3.

Another important advantage incident to my method is that by pressing ascreen on the wax or composition filled in on the original plate thecolor-printing surfaces may be stippled or screened fine or coarse, asdesired, and exactly the same results obtained lthereby as would be thecase were the old method employed-that is, stippling or screening thesaid color-printing surfaces by the aid of an engraving-tool oretching-and the said result is obtained without the aid of skilledlabor, as

the skill of an engraver or etcher is thereby entirely dispensed with.One of the screens or stippled surfaces is indicated by 5X in Fig. 3.

After the original plate is treated in the manner before described acopper shell thereof is formed by electrotyping in the usual way, sincethe composition or filling a hardens when it sets, so as to permit o felectrotyping. The electrotype-shell is then backed up and finished, aswould be the case with an ordinary electrotype-plate, the differencebetween the old method and my method of producing color-plates beingwholly in the preparation of the plate for the color-work.

Since in the present method of preparing color-plates it is necessary totransfer all colors on a separate plate, which plate is then engraved oretched before being ready for electrotyping, it follows that as the saidrequirements are not necessary in my method a great saving of time iseffected in making the form ready for color-printing, for the reasonthat in my method the work of removing those portions of the plate notto appear in color on the print is done in wax or other composition andeasily scraped away from the hard metal. The expense of preparing theplate is by my method greatly reduced, as in the practical applicationof the same Iliave found it possible to turn out twelve plates by mymethod in the time required to turn out one plate by the old method.

' Having thus described my invention, what I claim, and desire to secureby Letters Patent, is-

l. The method of preparing an original relief-plate for the purposesdescribed which embodies the following steps: first, applying a fillingof wax or other similar composition to the surface of the said originalrelief-plate, smoothing the said filling in the plane parallel with thesaid surface; second, removing' the said filling from those parts of theoriginal relief-plate not to appear in color on the print ,which may bemade from the plate, as set forth.

2. A method of preparing an original reliefplate for the purposesdescribed, which consists in, first, applying a layer of yieldingplastic material, capable of resisting heat, and smoothing said material'in a parallel plane with and slightly above the printing-surface,.

and second, removing the said material from those parts of the platewhich are not to appear in color, upon the print which may be made fromthe finished plate, as specified.V

3. A method of preparing an original reliefplate for the purposesdescribed-which consists in, first, applying a filling of plasticmaterial capable of resisting heat on the printfilling on theimpression-surface thereof which 1 covers all that portion of the plateto be utili ized as a color-printing surface, as set forth.`

6. A relief-plate of the character described, having a plastic fillingon aportion of the 'impressionsurface Whose printing-face is in a planeparallel with and slightly above the remaining portion of theimpression-surface of the relief-plate that is free of the filling, as

set forth.

CHRIS N. SMlTH'. Witnesses:

Gr. B. RICHARDSON, LoUIs H. POTTER.

IOO

